I'm going to take a little break from my normal sarcastic treatment of math and color science to share an infrequent hobby of mine - making sarcastic comments about people and companies that prey on the gullibility of consumers to sell "health" products.
Twinkies and other health food
Twinkies and other health food
I hate to admit this, but I was in a health food store last week. As you probably know, Twinkies are no longer being manufactured, since the parent company, Hostess, went out of business. I heard a rumor that a local health food store had found a few cases of the delectable snacks. Like the lemming that I am, I went running to the store. Well, not actually running. I drove my car. It was three blocks.
"Low Glycemic" sugar
I came across this bag of sugar that caught my attention, despite my panic stricken, crazed state of anxiety. "What? It's sugar? Like, real sugar? And it has a low glycemic index???" I had to learn more about this.
This is not Peter Bergman, who made the famous TV commercial about not being a doctor
But before I pontificate, I need to recite a disclaimer. I am not a doctor, but I saw a TV show once that featured someone else who was not a doctor. And I was met someone who read a book that said something about glycemic index.
The glycemic index (abbreviated GI) is much like the Dow Jones index, in that it goes up and down chaotically in response to any minor stimulation. In the Dow Jones Index, the stimulus is usually something like Obama passing gas or Fox News reporting about Obama passing gas. The GI is actually more about blood sugar levels then passing gas. When you eat something with a high GI (something with lots of sugar or simple carbs), your blood sugar spikes upward, giving you a sugar rush that we normally associate with people who write blogs. Then your body overreacts to this overreaction by pumping in the insulin, and you get a sudden drop in blood sugar level that we normally associate with people bringing their dogs with them to guard the shopping cart full of Twinkies.
The GI is the relative degree that a food will initiate this sort of reaction. Ordinary table sugar has a GI of 65, and honey is 55. 
Bubblegum music has a glycemic index of 817
So, that said, I started reading the label of this miracle sugar that has a low GI. I read the whole label of this package. Nowhere on the package did it state the value of the GI for this sugar. Well, that's odd. A qualitative product claim that is not precisely quantified? That never happens! Especially not in a health food store!
It became pretty clear to me that I needed to research this important matter more than I needed to satisfy my Twinkie fix. I needed to dig deep into medical journals, making sure all the experiments were blinded properly, and all the t tests were done using normal tea. In short, I read the entry in Wikipedia on "palm sugar". This article said nothing about the GI.
You may not now this, but there is a little place to click on any Wikipedia entry that will give you the revision history of the article. Just to the left of the search box in the upper right hand corner, there is a tab that says "View History". By reading through thrilling revision history, I can see that the very original version of the article (Dec of 2005) contained nothing at all related to GI. The first version that added this was on Christmas Eve, 2009. There was a lot of new material added, including the statement that palm sugar is "One of the lowest glycemic index sweeteners on the market".
This language was modified over numerous revisions. It soon received the "needs citation" award. Finally on Feb 27, 2011, someone got ticked off, and chucked out a lot of material, saying that they were "Remov[ing] commercial marketing links & dubious, uncited claims." Wow. That's what happens when you try to fool Wikipedia!
Hmmmmm..... It would appear that there might not be agreement on the GI for this sugar.
Cool pic from the Big Tree Farms website
What does the sugar company say?
For my next stop, I had a look at the website for the company that sells the sugar. On their website they actually affix a number to the GI.
"Coconut palm Sugar is naturally low on the Glycemic Index (GI), which has benefits for weight control and improving glucose and lipid levels in people with diabetes (type 1 and type 2). Coconut palm sugars are rated as a GI 35. By comparison, most commercial Agaves are GI 42, Honeys are GI 55 and Cane Sugars are GI 68."
Ok... interesting. Is there an attribution for this? Do they cite research or a source for this information? Actually, they do cite an organization. They describe the method used by the Philippine Food and Nutrition Research Institute. Ahh good. Now we are getting somewhere. I clicked on the link they provided, expecting to get the low down. Unfortunately, the link is to the main page of the website.
So I did some searching on this website. Every search I could think of came up empty handed.
Search results for "palm sugar glycemic"
This is starting to look not so good. I started searching the internet in general. I came across a very scientifical looking graph that clearly is the output of some very scientifical work. As proof of the scientificalness, I draw your attention to the legend of the graph (on the right), which is in Brush Script font. This font, originally designed for use on album covers with seascape sunsets, has become very popular of late in technical journals. The school bus yellow font color has also proven very effective in black and white journals.
Lest I be misunderstood in my very subtle sarcasm, let be a but more precise. I have no doubt that the graph came from a reputable paper investigating glycemic index. Two things raise my skeptical flag: 1) The image is highly photoshopped. 2) There is no reference on this webpage to the authors of the paper, the journal where this was published, nor even the year it was published. There is no way for me to find the paper.
I stumbled on this webpage that is rather critical of the coconut palm sugar industry. The bellicose author of this article went so far as to say that "many of the nutrient claims [of coconut palm sugar] may be unfounded." These are truly fighting words. I should point out that the bellicose author offered nothing to support this statement. There was no statement even of which claims may be unfounded. Pardon me for being didactic, but Dear Bellicose Author, Your statement about the unfounded claims is unfounded. I think it is likely true, but I gosh darn would like to see a bit more flesh on that drumstick.
I have often said that a good bellicose web post is worth an egregious rebuttal. Sure enough, I found one.
Fact: Findings were made by a national scientific agency (i.e. Department of Science and Technology/Food Nutrition and Research Institute) using internationally recognized protocols instituted by the University of Sydney (for GI testing).
What are the author's qualifications to dispute the findings of a national scientific agency such as the Philippine Food and Nutrition Research Institute (PNFRI)? Is the author an academic or a scientist who is in a position to scientifically contest the validity of Glycemic Index (GI) effect studies by the University of Sydney that is accepted worldwide as a reliable, physiological-based food classification system? How much weight does writer's opinion carry against the expert opinion of Food and Agricultral Organization (FAO) of the United Nations (UN) committee endorsement of the GI method made as early as 1997?
I don't know about you, dear reader, but I find this amusing. This argument is of the form of "Einstein said that your hair is purple. What qualifications to you have to refute him?" This egregious rebuttalist would have a much easier time convincing me if he or she would actually point me to a research paper or some otherwise non-financially involved source of information. Maybe just a link to a web page on the PNFRI website that says "Coconut palm sugar has a low glycemic index"?
The bellicose versus the egregious
Without that, both of these statements are worthless in ascertaining the science.
I did a lot of digging and finally found a copy of an article from PNFRI: "Glycemic index of coco sugar", by Trinidad P. Trinidad, PhD. This technical paper is one page long. It describes an experiment with ten individuals to determine the GI of "coco sugar". I am guessing that this is the same thing as coconut palm sugar, since the Big Tree Farms website copied from this paper almost verbatim.
One page. It all sounds reasonable, but it is one page long. The details of the results are not given. No fancy graphs with Brush Script font. Nor is there any indication as to when the study was performed, or where the study was published. I went back to the PNFRI website and searched for the author's name. There were a number of listings but nothing on this particular paper. I searched further to find a reference to this paper. Here is a resume of publications by Dr. Trinidad. The paper in question is not listed. It looks like she has done some good work, but there is no indication that the "GI of Coco Sugar" paper has ever been officially published.
By the way, Google found the paper from Dr. Trinidad for me. The paper is on the Philippine Coconut Authority website. This is a Philippine government agency "that is tasked to develop the [coconut] industry to its full potential". They may well have contracted some good scientific research, but they are clearly not financially disinterested in the results. Oh... I searched the PCA website and could not find a link to the paper by Dr. Trinidad.
I honestly don't know what to make of this, but I have found absolutely no evidence of peer-reviewed science that backs up the claim that the GI of coconut palm sugar is 35, or even that it is low. What evidence there has not been made readily available.
I did find one interesting fact though. Fructose (which is a major ingredient in high fructose corn syrup) has an average glycemic index of 19. As everyone knows, the rampant use of high fructose corn syrup is the reason why otherwise intelligent people voted for Mitt Romney in the last election . So, maybe finding a sweetener with a low glycemic index is not such a panacea?
I would be remiss if I were to skip another piece of evidence that I turned up. Dr. Oz endorses coconut palm sugar. Clearly his endorsement trumps the complete lack of any peer reviewed research on coconut palm sugar. After all, Dr. Oz has informed the public of the miraculous weight loss potential of raspberry ketones, proved the age reversing effects of acai berries by putting lemon juice on apples, and has put all medical doctors out of business by explaining that you can heal yourself with a "medical intuitive".
 This dog is a dead ringer for my dog, Scrabble. Honest.
 If we get lactose from milk, and fructose from fruit, what type of sugar do we get from french fries? Why, potatose, of course!
 I need to clarify a few things here...
First, high fructose corn syrup is not the same as fructose. HFCS is a combination of water, fructose (with a GI of 19) and glucose (with a GI of 100). The GI of the two sugars balance out, so that Coca-Cola, which uses high fructose corn syrup as a sweetener, has a GI of around 58.
Second, HFCS got a bad rap not too long ago with allegations that the body metabolized fructose much differently than other sugars. This has come into question lately. It seems that the jury may still be out as to whether HFCS is worse than other sweeteners, but one thing is clear. Sugar is not a health food.
Third, I understand that papers investigating HFCIRVD (high fructose corn syrup induced Romney voting disorder) are still in peer review, pending publication in either the New England Journal of Medicine, or Mad Magazine, I forget which.